Ji Won Lee MD, Presenter: Nothing to Disclose

Byoung Wook Choi MD, Abstract Co-Author: Nothing to Disclose

Young Jin Kim MD, Abstract Co-Author: Nothing to Disclose

Hye-Jeong Lee MD, Abstract Co-Author: Nothing to Disclose

Jin Hur MD, Abstract Co-Author: Nothing to Disclose

Yeon Joo Jeong MD, Abstract Co-Author: Nothing to Disclose

Yoo Jin Hong MD, Abstract Co-Author: Nothing to Disclose

Hee-Young Kim PhD, Abstract Co-Author: Nothing to Disclose

The goal of our study was to (1) assess the association between cardiovascular risk factors and aortic unfolding (AU), which was defined as the farthest distance from ascending aorta to descending aorta at the level of the pulmonary artery bifurcation on axial CT image and to (2) determine the potential predictor role of this measurement on cardiovascular risks by using standard Framingham equations. We also tried to (3) determine normal limits for AU in a large population of asymptomatic, low-risk adult subjects.

We measured AU in 913 adult patients (19-82 years) who underwent coronary artery calcium CT scanning. We assessed the association between risk factors and AU by using multivariate regression analysis and the associations between AU and the calculated cardiovascular risks by using Pearson correlation analysis. For the distribution of normal values of AU, the mean, standard deviation, and upper normal limit were obtained in each group divided by gender, age, and BSA.

Age, gender, coronary calcium score, BMI, BSA, hypertension, LVH on EKG, and plasma creatine were exclusively associated with AU. All the calculated cardiovascular risks significantly increased proportional to AU (correlation coefficients; 0.58 - 0.66). After exclusion of subjects who had any risk factors associated with AU, 541 subjects were included for analysis of normal values of AU. Aortic unfolding increased with advancing age (9.68mm per decade, p < 0.0001), and increasing BSA (β= 29.259, p < 0.0001). Mean value of AU in male subjects was greater than that in female subjects in all age groups stratified by 10 years interval, but it was reversed when AU was standardized by BSA.

AU determined from a single measurement on CT was associated with the age, sex, calcium scoring, BMI, BSA, hypertension, LVH on EKG and plasma creatine and this measurement was highly related to cardiovascular risks as assessed by the standard Framingham equations. Normal limits of AU have been defined by age, gender, and BSA in large, low-risk subjects.

Assessment of AU was possible from gated noncontrast CT scans obtained for coronary calcium measurements. And this measurement was highly related to cardiovascular risks.

Lee, J, Choi, B, Kim, Y, Lee, H, Hur, J, Jeong, Y, Hong, Y, Kim, H, Normal Values of Aortic Unfolding: A Potential Risk Factor of Cardiovascular Disease.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12027126.html